Oriental Fruit Fly

Oriental Fruit Flies - showing male and female differences

The California Department of Food and Agriculture confirmed seven Oriental Fruit Fly (OFF) detections between the dates of September 13 through September 28, 2021 in San Jose.   These fruit flies were found within 4.5 miles of an agricultural production site, so a quarantine has been declared.   This quarantine will encompass approximately 115 square miles.    To find out if you are in the quarantine, visit CDFA’s website:  https://www.cdfa.ca.gov/plant/off/regulation.html#index

We ask all homeowners in the quarantine zone to not share their backyard fruit until the end of this quarantine.  The quarantine will last approximately 9 months. If you have fruit on your property, you may consume it.  If you find maggots in your fruit, please call the State’s Pest Hotline at: (800) 491-1899.

The State is deploying detection traps to monitor if there are any additional flies in the area.

Because seven flies were found, the State will treat approximately a 22 square mile area using the "male attractant" technique. This technique uses ground-based, spot applications of minute amounts of an organic insecticide and feeding attractant lure. The treatment is applied as small, dollar-sized spots on inanimate objects such as street trees and utility poles approximately 8 feet off the ground. The male fruit flies are attracted to these spots because of the lure and die from feeding on the mixture. The treatments are applied at heights that are typically inaccessible and cause minimal disruption to the public.

We have unfortunately been invaded by this pest several times over the past decade. Thankfully, the California Department of Food and Agriculture (CDFA) was able to successfully eradicate OFF each time using the male attractant technique.

The Oriental Fruit Fly is an exotic insect pest found throughout much of the mainland of southern Asia and neighboring islands. Distribution in the United States is restricted to the Hawaiian Islands. OFF is a pest of over 230 kinds of fruit and vegetables including citrus, grapes, stone fruits, apples, pears, avocado, pepper, and tomato.

These infestations are likely the result of contraband fruit smuggled into California. We ask all Californians not to bring fruit or vegetables back from your travels.  Please also speak to family and friends about not sending care packages of fruit from outside of California.  Exotic fruit flies impact not only our multi-billion-dollar agricultural industry but threaten California’s native and urban environments.

CDFA Website

For more information about the Oriental Fruit Fly, you can visit the California Department of Food and Agriculture’s website:





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